Loading cap question

[w1vtp]

I bought this 460 PF (the green one) 'cause the other one needed replacement.  However, I need advise on how to fasten it to the strap as illustrated

Ideas?

[WA1LGQ]

Why not do it like that vacuum cap? Wrap the strap around the pin and put a bolt, nut and a couple of washers on it. If it does not wrap well around the pin, you might have to put some kind of sleeve on the pin to make the diameter larger.

........Larry

[N8ETQ]

  My El-Cheapo Harbor Freight Tap and Die set has small die's from
6-32 , 8-32, 10-20 etc. If you could thread enough to get a couple
nuts on it it would look good.

/dan

[AB2EZ]

Al

Take a piece of 1/2 inch diameter aluminum rod, about 3/4" long. Drill a hole on axis just a little larger than the pin on the capacitor. Tap the hole at one end to accept a screw (to connect the copper strap to the top of the rod). Drill through the side of the rod, and tap that hole to accept a set screw. Now you have the equivalent of a plate cap with a threaded hole through the top.

Stu

[K5WLF]

I'm with Stu on this one. I'd make the axial hole in the Al rod as tight a "hand slip fit" as I could get it. Just to ensure as much contact surface as possible. Should work just fine.

ldb
K5WLF

[AB3L]

How about an electrical one hole lug. This one is rated for #2 to #14 wire, Cu-Al.

[KA2DZT]

Al,

I've seen that type in the past,  I can't remember how they were connected to.  Doorknob caps were made different ways.

If the post is silver plated brass, which it probably is,  just solder the strap to the post.  Possible the plain post was used for soldering.

I have a lot of doorknobs, I'll take a look for one like your's and see if I can tell what type connection was used.

IIRC Erie made most of them, I'll also check an Erie catalog.

Fred

[W2PFY]

Hi Al, I have had a similar problem for testing a tube without a tube socket. You can buy these at home depot in the electrical department. You would have to drill a hole in the strap and use a brass screw & nut. Update. Looks like you have the hole so now you just need the lug and hardware. There are two sizes, you would need the smaller one. If you can't find any, I'll send you one. In the picture, I'm using a stainless steel washer. The bar code number is 8378637197.

I liked Stu's suggestion as well but you may have a problem with dissimilar metals.

What is that your building?  

 

[KB2WIG]

T,
 Very woody way to test a tube.... ..

klc

[w1vtp]

<snip>

What is that your building?  

 

That's a 2 X 813 amplifier I got off Timtron

Al

[W2PFY]

will the lug work i suggested or others?

[KA2DZT]

Al,

I've seen that type in the past,  I can't remember how they were connected to.  Doorknob caps were made different ways.

If the post is silver plated brass, which it probably is,  just solder the strap to the post.  Possible the plain post was used for soldering.

I have a lot of doorknobs, I'll take a look for one like your's and see if I can tell what type connection was used.

IIRC Erie made most of them, I'll also check an Erie catalog.

Fred

Al,

I checked my catalog,  My memory failed me,  it was Centralab that made most of those doorknob caps.  Erie made VHF feed thru and bypass caps.  Eire, as well as Centralab,  made other caps too.  Other companies also made doorknobs.

I did find some doorknobs with that plain stud on them, even ones with a plain stud on both ends.  There must have been some sort of snap-in type connection made to them (much like a small fuse holder.

I still think you can solder the strap to the stud.

Fred

[w1vtp]

<snip>
Fred

<snip>
Fred

Thanks Fred

Thanks everyone -- I have some good ideas to work on now

Al

[WA1GFZ]

Al Home Depot sells copper screw lugs.